Humidifier



Nov. 1, 1966 H. ALLCORN, JR 3,

HUMIDIFIER Filed May 25, 1964 4 Sheets-Sheet l INVENTOR Lufiher H. ALLcorn Jr ATTORNEYS Nov. 1, 1966 L. H. ALLCORN, JR 3,282,575

HUMIDIFI ER Filed May 25, 1964 4 Sheets-Sheet 2 INVENTOR 4 )3 ML LUHIQF HALLcorn Jr BY MJJWRQ 1 ATTORNEYS L. H. ALLCORN, JR

Nov. 1, 1966 HUMIDIFIER 4 Sheets-Sheet 5 Filed May 25, 1964 INVENTUR Lu her H. ALLcorn Jr 14% ATTORNEYS Nov. 1, 1966 L, H. ALLCORN, JR

HUMIDIFIER 4 Sheets-Sheet 4 Filed May 25, 1964 INVENTOR Lufhe r- H. ALLcorn Jr 2,424 & PM

ATTORNI United States Patent 3,282,575 HUMIDIFIER Luther H. Allcorn, Jr., Lewisville, N.C., assignor to The Bahnson Company, Winston-Salem, N.C., a corporation of North Carolina Filed May 25, 1964, Ser. No. 369,760 7 Claims. (Cl. 26136) The present invention relates to humidifiers and more particularly to humidifier apparatus designed for installation within air handling duct-work to add moisture to the airstream which is moved by air handling means past the location where the humidifier is installed.

The type of humidifier to which the invention relates is one wherein a stream of water is discharged onto the surface of a motor-driven disc which rotates inside of an annular grid, the disc serving to distribute the water radially outward by centrifugal force and thence through the plates of the grid which then serves to break up the water into a fine mist that is then easily entrained in the airstream passing by the humidifier unit in the duct-work. A continuously operating pump unit within the humidifier serves to feed water to the distributing disc, and such of the water as is not entrained into the air stream upon its first passage through the grid is returned to the pump casing for re-pumping to the distributing disc. Make-up water is supplied to the pump in a substantially continuous manner, and the rate at which the make-up water is supplied is made adjustable so as to provide for alternative modes of operation, either as a wasteless type or as a constant drain type.

A humidifier operating on the wasteless principle is one which includes a relatively large water reservoir with a float-operated valve for bringing in make-up water. The same water passes the disc and grid sections of the humidifier for humidification many times in that the pump supplies water from the reservoir to the distributing disc at many times the rate at which the make-up water is supplied to the reservoir by the float-controlled valve. A humidifier operating on the constant drain principle is one wherein water from the pump is passed only once to the distributing grid. Such of the water as is not broken up and entrained by the air stream upon leaving the grid is not returned to the pump for re-circulation but rather is permitted to drain oil? and is lost. A humidifier operating on the wasteless principle is thus obviously more economical of water consumption than one operating on the constant drain principle. However, a humidifier operating on the wasteless principle suffers from the disadvantage of having a relatively large water reservoir which tends to collect a large amount of re-circulated dirt and trash. Thus, frequent cleaning is necessary in order to maintain the humidifier in a satisfactory operating condition. With a humidifier operating on the constant drain principle there is virtually no water reservoir and hence, there is no collection chamber within which dirt and trash can accumulate but this advantage is offset to some degree because of the continuous wastage of water.

The improved humidifier construction in accordance with the present invention combines the desirable features of both the wasteless and constant drain types and eliminates their respective disadvantages. More particularly, as will be later described in further detail, a comparatively small water reservoir is provided and this is constituted essentially by the pump chamber itself. The water in this reservoir is never allowed to become stagnant enough to deposit its solids out in the bottom of the pump. During periods of maximum evaporation, such as periods when the humidifier unit is being subjected to extremely dry or warmed air, it can operate on the waterless principle with all feed water being evapice orated into the air stream on the first pass over the distributing disc and associated grid. During conditions when evaporative potential is not so great, the feed water rate then exceeds slightly the evaporation rate and the excess is permitted to drain away to a sump or other disposal point which then serves to remove any dirt and trash that may have become deposited in the pump chamher.

The foregoing as well as other objects and advantages inherent in the invention will become more apparent from the following description of a preferred embodiment and the accompanying drawings wherein:

FIG. 1 is a perspective view of the improved humidifier unit as installed in an air duct;

FIG. 2 is a view generally in vertical section of the humidifier unit with certain parts shown in elevation;

FIG. 3 is a horizontal section taken on line 33 of FIG. 2;

FIG. 4 is a view in vertical section of that part of the humidifier unit which carries water from the pump chamber and discharges it onto the upper rotatable distributing disc;

FIG. 5 is a plan view of the pump chamber with its dual tangential outlets, one high and the other low; and

FIG. 6 is a view in elevation of the pump chamber.

With reference now to the drawings it will be seen that the improved humidifier unit, in its illustrated embodiment is especially adapted for mounting in an air duct 1. Generally speaking, water is delivered to atomizing units located respectively Within two pans 2 and 3 mounted in superposed spaced relation and the atomized particles become entrained in the air stream which is carried past the humidifier in the air duct 1.

The structural details of the pans and atomizing units and the supporting structure are shown more clearly in FIG. 2. Here it will be seen that the humidifier unit comprises a base plate 4 which may have any suitable configuration. The one depicted in the drawing is rectangular and is mounted in a correspondingly configured opening cut into the bottom wall of the air duct 1. The peripheral portions of the plate overlap the marginal portions of the hole cut into bottom wall of the duct and a gasket 5 is used therebetw-een for cushioning purposes.

Secured to and depending from the lower face of the base plate 4 is an electric motor 6 having its armature shaft oriented vertically upward and coupled to a vertical drive shaft 6a. This shaft has secured to it a generally conically shaped pump rotor 7 and two superposed water distributing disc type impellers 8 and 9'. Impellet disc 8 is surrounded by a lower grid ring 10' and the upper impeller disc 9 is surrounded by an upper grid ring 11. Impeller disc 8 and its grid ring 10 are located in the lower pan 2 and impeller disc 9 and its grid ring 11 are located in the upper pan 3.

In a manner which will be explained later in further detail, Water is delivered from the pump unit into a discharge end of which is so located as to deliver water onto the upper surface of the upper impeller disc 9 from which it is thrown in generally radial outward directions by the developed centrifugal forces, the water being thrown into contact with the grid plates 11a and broken up into fine particles which then become entrained in the air passing through duct 1. Such of the water delivered through tube 12 that is not so broken up and atomized is collected in the bottom of pan 3 and flows by gravity towards the center thereof from which it passes downwardly through a central sleeved opening 13 provided in pan 3 for passage of the drive shaft 6a and the bushing 14 surrounding the same and which serves to maintain the two impeller discs in vertically spaced relation.

The water which comes down through the sleeved opening 13 is discharged onto the central portion of the lower distributing disc 8 and is again thrown in generally radially outward directions into contact with the plates 19a of grid ring 1t which serves to atomize the water and cause it to be entrained in the air stream.

Such of the water that is not entrained by the lower atomizing unit collects on the bottom of pan 2 and flows by gravity to the central part thereof from which it discharges downwardly into the cylindrical pump chamber arranged concentric with and surrounding the pump rotor 7.

The pump chamber 15 which is actually the interior of the pump housing is provided with upper and lower tangentially arranged wall outlets 16, 17 shown clearly in FIGS. 5 and 6 and also in FIG. 1 at smaller scale. The upper outlet 16 is connected to a drain tube 18 which is adapted to be connected by coupling 19 to any suitable Waste drain pipe. That is to say such of the Water as is discharged from the upper outlet 16 is drained away and not re-cycled through the humidifier.

The lower pump chamber outlet 17 is connected by means of a tube 20 into the bore 21 of a vertical post 22 which, as shown clearly in FIG. 4, is mounted on the base plate 4 and serves as one of three supports for the lower and upper pans 2, 3, as well as the lower and upper grid rings 10, 11. A needle valve assembly 23 fitted into the bore 21 of post 22 from the lower end is provided for adjusting the rate-of-fiow of water upwardly through the bore and through the discharge tube 12.

The two other supporting posts for the pans are designated by numerals 24, 25 and as is apparent from FIG. 3, all of the posts are arranged symmetrically i.e. 120 apart about the axis of drive shaft 6a.

Located within pump chamber 15 just above the lower tangential outlet 17 is a flat pump ring 26 which is seated in a peripheral groove 27 provided in the chamber wall, the ring being held in place by means of a retainer ring 28. The inner periphery of pump ring 26 is spaced slightly from the coned periphery of the pump rotor 7 and functions to force the pump discharge through the lower outlet 17.

In accordance with the improved construct-ion of the humidifier according to the present invention, as previously explained the comparatively small amount of space available within the pump chamber 15 itself constitutes the only reservoir for water. Within this relatively small space the water is constantly agitated by the pump rotor, and this constant agitation in conjunction with a positive drain through the upper wall outlet 16 prevents any settling-out of any particulate material within the pump chamber itself.

Water is supplied to the humidifier unit as shown in FIG. 3 from any suitable supply line 29, this line being connected in at the coupling 3t which is connected to the inlet of a strainer unit 31. The strainer outlet is connected through a manually set valve 32 which can be of the needle type if desired to another valve 33 of the on-ofi type and which is controlled by the solenoid unit 34. To the outlet from the solenoid controlled valve 33 is connected a tube 35 which leads into the bore 36 of post 24. Water coming in through tube 35 and bore 36 passes upward through the latter and is discharged laterally through a port 37 as shown in FIG. 1 onto the bottom of the lower pan 2 from which it flows by gravity into the upper, open end of the pump chamber 15.

Motor 6, and the other components located at the underside of plate 4 which project below the bottom wall of the air duct 1 are preferably enclosed by bowl-like housing 38 which can be held in position by any suitable means such as by a frictional fit of the peripheral edge portion of the housing into the groove of a retaining ring 39 fastened to the underside of base plate 4.

Operation The improved humidifier unit as it has been described operates in the following manner. As has been previously explained at the outset of the specification, a comparatively small water reservoir is provided and this is constituted by the pump chamber 15 itself. The water in this reservoir is never allowed to become stagnant enough to deposit its solids out in the bottom of the pump chamber. During periods of maximum evaporation, such as during periods when the humidifier unit is being subjected to extremely dry or warm air, it can operate essentially on the so-called wasteless principle or cycle in which all feed water is atomized and entrained into the air stream passing through duct 1 on the first pass over the upper and lower distributing discs 9, 8 and associated grids 11 and 10. During conditions when evaporative .potential is not so great, the feed water rate can then exceed slightly the evaporation or entraining rate, and the excess is permitted to drain off through tube 18 which then serves to remove any dirt or trash that may have become deposited in the pump chamber 15.

The solenoid unit 34 controlling valve 33 functions in the known manner to cut the water supply to the humidifier unit either on or oif as a function of the humidity condition desired to be maintained in the space served by air duct 1. This provides an automatic type of control but which, however, is not essential to operation of the humidifier unit.

The manually controlled inlet valve 32 is desirable to provide a manual control over the rate-of-flow of makeup water which flows upwardly through hollow post 24 and is discharged into the lower pan 2 and thence into pump chamber 15.

Thus, depending upon the variable factors involved, more or less water will always be present in the pump chamber 15 thus determining its level and thus determining how much, if any, of the water supplied to the unit is constantly drained away through the upper pump chamber outlet 16 and drain tube 18.

In conclusion, while a preferred embodiment of the improved humidifier unit has been described and illustrated, vanious modifications in the construction and arrangement of components may be adopted without, however, departing from the spirit and scope of the invention as defined in the appended claims.

I claim:

1. A humidifier comprising a motor driven atomizer unit adapted to be placed within an air duct for entraining atomized water into an air stream passing through the duct, a-pump, said pump including a motor driven rotor rotatable in an upright pump chamber located below said atomizer unit, said pump chamber constituting the only reservoir for water within said humidifier and including in the wall thereof upper and lower positioned outlets, said upper outlet being connected to a drain tube and said lower outlet being connected to a feed tube delivering water upwardly to said atomizer unit as a result of being forced out of said lower wall outlet by rotation of said pump rotor, means providing a gravity return flow for such atomized water as is not entrained in said air stream into said pump chamber for re-cycling and the level of the water in said pump chamber being determinative of the amount of overflow water removed from the humidifier through said upper wall outlet and drain tube.

2. A humidifier comprising an atomizer unit adapted to be placed Within an air duct for entraining atomized water into an air stream passing through the duct, said atomizer unit including a motor driven water distributing disc rotatable Within an annular grid, a pan disposed beneath said atomizer unit for collecting such atomized water as is not entrained in said air stream, a pump, said pump including a motor driven rotor rotatable in an upright pump chamber located below said pan and said pan including a discharge opening through which water collected therein is returned by gravity flow to said pump chamber for re-cycling, said pump chamber constituting the only reservoir for water within said humidifier and including in the wall thereof upper and lower positioned outlets, said upper outlet being connected to a drain tube and said lower outlet being connected to a feed tube delivering water upwardly to a point of discharge adjacent said distributing disc of said atomizer unit as a result of being forced out of said lower wall outlet by rotation of said pump rotor, the level of the water in said pump chamber being determinative of the amount of overflow water removed from the humidifier through said upper wall outlet and drain tube.

3. A humidifier comprising an atomizer unit adapted to be placed within an air duct for entrain-ing atomized water into an air stream passing through the duct, said atomizer unit including a motor driven water distributing disc rotatable within an annular grid, a pan disposed beneath said atomizer unit for collecting such atomized water as is not entrained in said air stream, a pump, said pump including a motor driven conic like rotor rotatable about a vertical axis in an upright pump chamber located below said pan and said pan including a centrally located discharge opening through which water collected therein is returned by gravity flow into said pump chamber for re-cycling, said pump chamber constituting the only reservoir for water within said humidifier and including in the wall thereof an upper outlet connected to a drain tube and a lower outlet connected to a feed tube delivering water upwardly to a point of discharge adjacent said distributing disc of said atomizer unit as a result of being forced out of said lower wall outlet by rotation of said pump rotor, and a horizontally positioned annular pump ring located in the lower portion of said pump chamber in spaced relation to the periphery of said pump rotor but above the level of said lower wall outlet for forcing the pump discharge through said lower Wall outlet, the level of the water in said pump chamber being determinative of the amount of overflow water removed from the humidifier through said upper wall outlet and drain tube.

4. A humidifier comprising an atomizer unit adapted to be placed Within an air duct for entraining atomized water into an air stream passing through the duct, said atomizer unit including a pair of superposed motor driven water distributing discs each of which is rotatable within an annular grid, a pan disposed beneath each said disc and its associated grid for collecting such atomized water as is not entrained in said air stream, a pump, said pump including a motor driven rotor rotatable about a vertical axis in an upright pump chamber located below the lowermost pan and which latter includes a centrally located discharge opening through which water collected therein is returned by gravity flow into said pump chamber for re-cycling, the uppermost pan also including a centrally located discharge opening through which water is discharged onto the lowermost distributing disc, said pump chamber constituting the only reservoir for water within said humidifier and including in the wall thereof an upper outlet connected to a drain tube and a lower outlet connected to a feed tube delivering water upwardly to a point of discharge adjacent the uppermost distributing disc as a result of being forced out of said lower wall outlet by rotation of said pump rotor, the level of the Water in said pump chamber being determinative of the amount of overflow water removed from the humidifier through said upper wall outlet and drain tube 5. A humidifier as defined in claim 4 wherein said pump rotor has a conic like configuration and said pump chamber includes a horizontally positioned annular pump ring located in the lower portion of said pump chamber in spaced relation to the periphery of said pump rotor but above the level of said lower outlet for forcing the pump discharge through said lower outlet. 1

6. A humidifier as defined in claim 4 and which further includes a plurality of upright posts spaced about the rotational axis of said distributing discs and which serve to support said annular grids and associated pans, one of said posts being hollow and serving as part of said feed tube delivering water from the lower outlet of said pump chamber to the discharge |point adjacent said uppermost distributing disc, and another of said posts also being hollow and serving to convey make-up water into the lowermost pan from an external water supply source.

7. A humidifier as defined in claim 4 wherein said distributor discs and pump rotor are secured to a common upright drive shaft driven by an electric motor, said drive shaft passing centrally through said pump chamber and said superposed pans.

References Cited by the Examiner UNITED STATES PATENTS 1,957,316 5/1934 Buckley et al. 261-91 1,993,299 3/1935 Brott 26191 2,149,921 3/1939 Lea 26191 X 2,181,801 11/1939 Davison et a1. 26l-91 2,827,270 3/ 1958 Martin 26129 3,055,645 9/1962 Feldermann 261-91 X 3,193,261 7/1965 Nesbitt 261-89 X HARRY B. THORNTON, Primary Examiner.

T. R. MILES, Assistant Examiner. 

1. A HUMIDIFIER COMPRISING A MOTOR DRIVEN ATOMIZER UNIT ADAPTED TO BE PLACED WITHIN AN AIR DUCT FOR ENTRAINING ATOMIZED WATER INTO AN AIR STREAM PASSING THROUGH THE DUCT, A PUMP, SAID PUMP INCLUDING A MOTOR DRIVEN ROTOR ROTATABLE IN AN UPRIGHT PUMP CHAMBER LOCATED BELOW SAID ATOMIZER UNIT, SAID PUMP CHAMBER CONSTITUTING THE ONLY RESERVOIR FOR WATER WITHIN SAID HUMIDIFIER AND INCLUDING IN THE WALL THEREOF UPPER AND LOWER POSITIONED OUTLETS, SAID UPPER OUTLET BEING COCONNECTED TO A DRAIN TUBE AND SAID LOWER OUTLET BEING CONNECTED TO A FEED TUBE DELIVERING WATER UPWARDLY TO SAID ATOMIZER UNIT AS A RESULT OF BEING FORCED OUT OF SAID LOWER WALL OUTLET BY ROTATION OF SAID PUMP ROTOR, MEANS PROVIDING A GRAVITY RETURN FLOW FOR SUCH ATOMIZED WATER AS IS NOT ENTRAINED IN SAID AIR STREAM INTO SAID PUMP CHAMBER FOR RE-CYCLING AND THE LEVEL OF THE WATER IN SAID PUMP CHAMBER BEING DETERMINATIVE OF THE AMOUNT OF OVERFLOW WATER REMOVED FROM THE HUMIDIFIER THROUGH SAID UPPER WALL OUTLET AND DRAIN TUBE. 